An asphalt driveway may appear to be solid and impervious, especially if you take a fall on it. The truth is that a driveway is designed to have a certain amount of give to it. A flexible asphalt driveway can give way to pressure then bounce back without cracking. It can also cope with the cycle of expanding and contracting that stems from the cycle of heating and cooling your driveway is subject to. Unfortunately, an asphalt driveway can lose its flexibility as it ages. In order to get the most life from your driveway, you need to use a sealcoat to protect it.
After prolonged exposure, the sun's UV rays can bake the residual liquids left in asphalt after it cools out of your driveway. As this happens, your driveway will become brittle and lose its ability to respond to pressure. Nothing more than a cycle of expanding and contracting can cause cracks to start to form in your driveway, and heavy loads can make these cracks worse. A sealcoat will absorb the sun's rays before they have a chance to do damage to your driveway.
A second danger that a driveway has to contend with is posed by the solvents in petroleum products. If you fill up your lawnmower on your driveway and spill gas, or you have a motorcycle that leaks oil, the solvents in these products can break down the tar that holds your driveway together and cause pebbles to start to separate. Thus, potholes are born. A sealcoat will stop the chemicals before they can damage your driveway.
Water will do little to hurt your driveway until temperatures drop below freezing. As water settles into the cracks and depressions in your driveway, then freezes, it will expand. Expanding ice creates a wedging effect that can cause new cracks and make old cracks worse. A sealcoat will fill in the divots between pebbles in your driveway and seal out water before it has a chance to work down into your driveway.
You might be tempted to look at installing a sealcoat on your driveway as an extra cost, but this is not the case. A sealcoat is one of the best options available for protecting your driveway from damage. Besides, it is much cheaper to have workers (such as those from Home Outdoor) cover your driveway with a sealcoat than to replace your driveway once it is beyond repair.